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View Full Version : failed a smog test...



snoopyloopy
05-10-2007, 03:47 PM
...miserably. i'm apparently driving a gross polluter. refer to the pic, but basically, my car is putting out too much hc and far too much co. so where should i start? the smog ref suggested that my coolant temp sensor might be bad and i have actually been getting that exact cel for over a year now. so i went ahead and changed that, but i haven't gone back up there yet. also took off my short ram because it's actually illegal and he wasn't even supposed to smog me. but high flow cat is still on the car because it's a pain to change the exhaust...

http://i5.photobucket.com/albums/y185/snoopyloopy/car/accord/smogtestresults0001.jpg

MessyHonda
05-10-2007, 05:41 PM
holy smokes......time to seafoam it and get it tuned up...change the oil....and run some premium gas next time you take it in.

Estimated Prophet
05-10-2007, 05:58 PM
I passed with flying colors on a magnaflo cat, so I wouldn't worry about that. I'd do what Messy suggested. My test was the opposite of yours, my Nox was hella high and the others were all low.

What cat do you have by the way?

cubert
05-10-2007, 06:49 PM
move somewhere that doesnt have emissions.

MessyHonda
05-10-2007, 07:04 PM
move somewhere that doesnt have emissions.



no....cali just has to remove all this stuff......i would not like to live anywhere else.....i live like 3 hours away from snow.....6 hours from so-cal and i live in the bay area with 7 mill people

cygnus x-1
05-10-2007, 08:25 PM
High CO means the combustion temperature is too cold. Could be that temp sensor. Also could be weak ignition. I would do the standard tune up stuff as well, distributor cap/rotor/wires, spark plugs; maybe some seafoam.

C|

Ichiban
05-10-2007, 08:33 PM
Sounds like its rich. High CO= cold chamber+excess fuel or poor combustion. My guess is the temp sensor isn't telling the computer the engine is hot and it's still dumping in fuel. Could also test for injector leakage and check timing as well. Being too retarded could raise CO levels, take it as you may...Being too advanced (and lean) will drop HC and CO and raise NOX. As cylinder temperature dictates NOX formation, from your readings I'd agree that it's running on the cold side. The high HC and CO indicates excess fuel, which cools the combustion process. As the CO is also high, it indicates that combustion is taking place, as compared to a misfire situation that would display high HC but no CO, as CO is a by-product of incomplete combustion.

Or an O2 sensor has gone awry....

Whatever the cause, all signs point to a rich mixture.


Edit: I just read an interesting article:http://www.epa.state.oh.us/dapc/echeck/docs/techtalk_sum02.pdf

shepherd79
05-11-2007, 04:47 AM
before you go back to retest, make sure you drive for at least 30 minutes at highway speed. this will fully warm up the cat and other sensors.

As far as tune up goes: this is what I would do in your place.

1. new thermostat (oem one from honda)
2. new plugs
3. new wires
4. distributor cap and rotor button.
5. recheck all the emission vacuum lines and make sure they are working correctly.
6. clean out EGR sensor and make sure it is holding the vacuum.

if you don't pass after that, your cat has to go.

snoopyloopy
05-11-2007, 06:32 AM
Sounds like its rich. High CO= cold chamber+excess fuel or poor combustion. My guess is the temp sensor isn't telling the computer the engine is hot and it's still dumping in fuel. Could also test for injector leakage and check timing as well. Being too retarded could raise CO levels, take it as you may...Being too advanced (and lean) will drop HC and CO and raise NOX. As cylinder temperature dictates NOX formation, from your readings I'd agree that it's running on the cold side. The high HC and CO indicates excess fuel, which cools the combustion process. As the CO is also high, it indicates that combustion is taking place, as compared to a misfire situation that would display high HC but no CO, as CO is a by-product of incomplete combustion.

Or an O2 sensor has gone awry....

Whatever the cause, all signs point to a rich mixture.


Edit: I just read an interesting article:http://www.epa.state.oh.us/dapc/echeck/docs/techtalk_sum02.pdf
hmmm. yeah, that's exactly what he said. it's probably thinking it's cold and dumping in too much fuel. and the timing was off as well. on the other page of the report, he put down that it was defective (23 btdc). so i'm guess that's where it was. so i've adjusted the timing, and it doesn't backfire as much or in the same part of the rpm range. as well as changed that sensor, and new plugs. i'll see if i can't get a tank of some really high octane for the test too. so i'm hoping that's it. but hopefully, i can coerce the state to pay for my repairs if i need any more.


no....cali just has to remove all this stuff......i would not like to live anywhere else.....i live like 3 hours away from snow.....6 hours from so-cal and i live in the bay area with 7 mill people
yeah, i love socal. you can go wakeboarding in the morning, head up the mountain for some snowboarding, back down for some skateboarding and finish the day off at the beach with some surfing...where else can you do that?



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HERE IS A LIST OF THINGS YOU MIGHT TAKE A LOOK AT
Check for Vacuum leaks
- Intake Manifold Gasket
- Vacuum lines
- Gaskets Carb/EFI
- PCV Valve
Check your oil system
- Oil Level
- Oil Filter
- Oil Weight
Check the coolant system
- Radiator Fluid Level
- Thermostat
- Fans / Thermoswitch / Coolant Temp Sensor
- Waterpump
- Check your engine temperature
- Does the engine heat up to normal operating temp?
- Does the engine overheat?
Check Ignition
- Plugs
- Wires
- Ground Wires ( Battery / thermostat / radiator support )
- Cap / Rotor
- Ignition Timing
Check ECU
Check Fuel System / A/F Mixture
- Float Level (Carb)
- Injectors (EFI)
- Pressure Regulator (EFI)
- Fuel Filters
- Fuel Pump
- AS Valve (Carb)
- A/F Screw (Carb)
- Cut-Off Solenoid (Carb)
Emissions System
- O2 Sensor
- EGR Valve
- Catalytic Convertor

.
.
.


Methods to help reduce NOX , HC ( Hydrocarbons ) , CO ( Carbon Monoxide )

:KEY:
#) Solution
--- Problem it addresses
-- More Related Solutions

0) Ignition Sytem . make sure it's working properly
--- High HC from poor ignition

1) Retard ignition timing to give more combustion time
--- High HC from incomplete combustion

2) Compression , Compression Ratio , Fuel Octane
--- High HC from poor compression
-- Change Fuel Octane
-- Check Engine Compression

3) LEAN A/F mixture to increase engine temp
--- High HC from lean mixture

4) RICH A/F mixture to decrease engine temp
--- This may increase HC or CO
--- High CO from a rich mixture
--- Too Rich a mixture can melt the Cat

5) EGR
--- NOX reduced by the EGR
--- EGR lowers the combustion temperature

-----

High NoX is usually directly related to the EGR. Very common on the 4th gens since the EGR ports get clogged very easily. I'm not sure if it will harshly change other readings though. Probably want to hook it up again to be safe.
- Clogged EGR passage

If your high flow cat is a "real" good quality high flow cat, then in most cases I've seen, it should get lower readings than the original cat. If it's just a test pipe or a cheaply made CC, then that might be your cause. Could also be your O2 sensor.
- Catalytic Convertor
- O2 Sensor

If I have trouble passing emissions here in BC, I usually get high octane gas, dump some more octane booster in it, retard the timing, make sure the car is tuned up, and drive the car atleast 30 minutes on the freeway or something before going to testing.
- Octane

stereo
05-11-2007, 11:37 PM
those are some strange readings as most of these cars will pass everything but the NOx but in your case you are going to have to fix the backfire problem since it was burning that rich it's most likely fouled the plugs O2 sensor and even the cat. it seems like the engine is not reaching operating tempature thus the computer is staying in open loop. also check the vacuum advance as that can be the cause for the timing problem.